This invention relates to a design for a silent valve and belongs to the group of water-sanitary armatures for all kinds of fluids. According to the International Patent Classification, this invention is classified into the group F 16K 1/02, relating to opening regulation and closing the flow of liquids.
Known valves, for instance valves for household use, which have a thread and nut and a seal pressing against a valve seat, have shown a series of disadvantages. One disadvantage is that known designs allow too strong or too weak compression of the seal against the valve seat, leading to valve seat erosion. A common effect is leaking, which requires machining the valve seat, as for example bibb seat reaming, which operation can be done only a relatively few times before the valve is rendered unfit for further service.
Another disadvantage of known valves is in the fact that very significant friction and erosion may occur between the thread and nut, resulting in malfunction of the entire assembly. Such friction causes enlargement of the clearance between thread and nut, permitting the moving parts of the valve to vibrate in response to fluid pressure, which causes hydraulic shocks to the whole installation along with undesirable noise. Such noise may occur with or without cavitation.
Still another disadvantage of known valves is that fact that often all the parts of the valve are made of the same kind of material, so that, when the valve is out of service for some time, or if the temperature difference is too high, valve operation can be blocked because of seizing or interference between parts.
It is the object of this invention to provide a valve design which will close the fluid flow efficiently, without cavitation, and which is noiseless when opened and block-proof even after a prolonged out-of-service period.